1. Field of the Invention
The present invention relates to a braking force control system of a vehicle which adequately distributes the braking force in braking.
2. Description of the Related Art
In recent years, there have been proposed various braking control systems which make use of constitutions of anti-lock braking systems (ABS) and control distribution of braking force in normal braking to be more adequate one.
For example, in JP-A-10-119744, there is disclosed one which independently increases, decreases or holds braking oil pressure of each of right and left rear wheels when deceleration of a vehicle reaches a specified value and when a vehicle speed exceeds a specified speed, so that braking force distribution between rear and front wheels becomes an approximately ideal one to perform independent braking control for carrying out sufficient braking.
Incidentally, in the ABS control and the braking force distribution control as described above which provide an independent braking for the rear wheel side, because of not so large transfer of a vertical load between the right side and left side wheels in a normal turning of the vehicle, an attitude of the vehicle does not change largely in rolling even when the brake is operated, so that the braking can be performed with a normal feeling of the rolling. However, in a high lateral acceleration turn on a high friction road, when the ABS control and braking force distribution control of the rear wheels are independently carried out, because of a large difference between the right and left vertical loads, there is a fear that unpleasant rolling behavior of the vehicle body is occurred due to a change in braking force of the turning outside rear wheel caused by each of the braking controls.